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	<head>
		<title>three.js webgl - THREE.PointLight ShadowMap</title>
		<meta charset="utf-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
		<link type="text/css" rel="stylesheet" href="main.css">
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		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - THREE.PointLight ShadowMap by <a href="https://github.com/mkkellogg" target="_blank" rel="noopener">mkkellogg</a>
		</div>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';

			import Stats from 'three/addons/libs/stats.module.js';

			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';

			let camera, scene, renderer, stats;
			let pointLight, pointLight2;

			init();

			function init() {

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 1, 1000 );
				camera.position.set( 0, 10, 40 );

				scene = new THREE.Scene();
				scene.add( new THREE.AmbientLight( 0x111122, 3 ) );

				// lights

				function createLight( color ) {

					const intensity = 200;

					const light = new THREE.PointLight( color, intensity, 20 );
					light.castShadow = true;
					light.shadow.bias = - 0.005; // reduces self-shadowing on double-sided objects

					let geometry = new THREE.SphereGeometry( 0.3, 12, 6 );
					let material = new THREE.MeshBasicMaterial( { color: color } );
					material.color.multiplyScalar( intensity );
					let sphere = new THREE.Mesh( geometry, material );
					light.add( sphere );

					const texture = new THREE.CanvasTexture( generateTexture() );
					texture.magFilter = THREE.NearestFilter;
					texture.wrapT = THREE.RepeatWrapping;
					texture.wrapS = THREE.RepeatWrapping;
					texture.repeat.set( 1, 4.5 );

					geometry = new THREE.SphereGeometry( 2, 32, 8 );
					material = new THREE.MeshPhongMaterial( {
						side: THREE.DoubleSide,
						alphaMap: texture,
						alphaTest: 0.5
					} );

					sphere = new THREE.Mesh( geometry, material );
					sphere.castShadow = true;
					sphere.receiveShadow = true;
					light.add( sphere );

					return light;

				}

				pointLight = createLight( 0x0088ff );
				scene.add( pointLight );

				pointLight2 = createLight( 0xff8888 );
				scene.add( pointLight2 );
				//

				const geometry = new THREE.BoxGeometry( 30, 30, 30 );

				const material = new THREE.MeshPhongMaterial( {
					color: 0xa0adaf,
					shininess: 10,
					specular: 0x111111,
					side: THREE.BackSide
				} );

				const mesh = new THREE.Mesh( geometry, material );
				mesh.position.y = 10;
				mesh.receiveShadow = true;
				scene.add( mesh );

				//

				renderer = new THREE.WebGLRenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( animate );
				renderer.shadowMap.enabled = true;
				renderer.shadowMap.type = THREE.BasicShadowMap;
				document.body.appendChild( renderer.domElement );

				const controls = new OrbitControls( camera, renderer.domElement );
				controls.target.set( 0, 10, 0 );
				controls.update();

				stats = new Stats();
				document.body.appendChild( stats.dom );

				//

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			function generateTexture() {

				const canvas = document.createElement( 'canvas' );
				canvas.width = 2;
				canvas.height = 2;

				const context = canvas.getContext( '2d' );
				context.fillStyle = 'white';
				context.fillRect( 0, 1, 2, 1 );

				return canvas;

			}

			function animate() {

				let time = performance.now() * 0.001;

				pointLight.position.x = Math.sin( time * 0.6 ) * 9;
				pointLight.position.y = Math.sin( time * 0.7 ) * 9 + 6;
				pointLight.position.z = Math.sin( time * 0.8 ) * 9;

				pointLight.rotation.x = time;
				pointLight.rotation.z = time;

				time += 10000;

				pointLight2.position.x = Math.sin( time * 0.6 ) * 9;
				pointLight2.position.y = Math.sin( time * 0.7 ) * 9 + 6;
				pointLight2.position.z = Math.sin( time * 0.8 ) * 9;

				pointLight2.rotation.x = time;
				pointLight2.rotation.z = time;

				renderer.render( scene, camera );

				stats.update();

			}

		</script>
	</body>
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